If a joke was what it ever was, then how do you explain the following?

One which cannot fall into the abyss, of which the fundamentalists of metaphysics prattle – it is not that of agile sophistics but that of insanity – turns, under the commandment of its principle of security, analytical, potentially into tautology.

Dont you see this as a suggestion, to "fall into the abyss"? Doesn't he say that those that don't do that, will turn to analytical and tautological statements? What is an abyss, if not something bottomless?

Only those thoughts which go to extremes can face up to the all-powerful powerlessness of certain agreement; only mental acrobatics relate to the thing, which according to the fable convenu
[French: agreed-upon fiction] it holds in contempt for the sake of its self-satisfaction.

Doesn't he say here that it is with mental acrobatics that one should approach the extremes? And that the herd will see these moves as nothing more than self satisfied rhetoric, as perhaps it was done with Nietzsche?

Another reference to abyss and bottomless:

In contrast to this, the cognition throws itself à fond perdu [French: into the depths] at objects, so as to be fruitful. The vertigo which this creates is an index veri [Latin: index of truth]; the shock of the revelation, the negativity, or what it necessarily seems to be amidst what is hidden and monotonous, untruth only for the untrue.

Also, as per your suggestion, I had a look at the lectures. The notes on this passage say:

Truth [to be found] only in whatever throws itself away without safety belt, à fonds perdu.

I want to condense Against Relativism in a facetious manner:

Relativism is something which ND opposes.

Not in the way that others do, because (various reasons)

The points I think that are important here are that ND is against relativism, and this is a long overdue time for ND to transition from the epistemic to the ethical.

It would be more fruitful to cognize relativism as a delimited
form of consciousness.

Sums up his take on the bourgeois form of relativism, I think: Rather than producing arguments against it one can, from a philosophical vantage, see that such kinds of relativism or skepticism aren't worth addressing: But that's not to say that skepticism is not worth addressing (as Adorno has already done)

I'm more inclined to see this as a straight expression, but I don't know. It seems hard to reconcile the notion that Adorno is making fun of this idea while also noting how the place where ontology hits bottomlessness is the place of truth. — Moliere

Where's the difficulty? Think of it as I said, when ontology hits (the bottom of) bottomlessness, there it finds truth. In other words, ontology never finds truth. And, contrary to those who think that truth is never hidden from us, Adorno seems to think it is always hidden from us.

I have a hard time reading this like he's poking fun. — Moliere

Well he has already said that there is humour involved in philosophy.

Dont you see this as a suggestion, to "fall into the abyss"? Doesn't he say that those that don't do that, will turn to analytical and tautological statements? What is an abyss, if not something bottomless? — Pussycat

i don't see your point. When he says that, he is talking about those who think that truth cannot hide from us. That whole paragraph, from which you quoted, is all part and package of that sarcasm involving the relationship between truth and groundlessness. To avoid groundlessness we choose tautology, but tautology is useless, powerless. So metaphysics is nothing but the insane prattle of going from one extreme to the other.

Doesn't he say here that it is with mental acrobatics that one should approach the extremes? And that the herd will see these moves as nothing more than self satisfied rhetoric, as perhaps it was done with Nietzsche? — Pussycat

He's sarcastically making fun of metaphysics. It's mental acrobatics, yes, but it is doing nothing (Wittgenstein's idleness) but insane, ridiculous moves, which we might be entertained by (laugh at). These acrobatic moves are even beyond sophistry in ridiculousness, because at least the agility of sophistry is purposefully directed.

Where's the difficulty? Think of it as I said, when ontology hits (the bottom of) bottomlessness, there it finds truth. In other words, ontology never finds truth. And, contrary to those who think that truth is never hidden from us, Adorno seems to think it is always hidden from us. — Metaphysician Undercover

Probably in us talking past one another in some sense, somewhere.

I don't think I or @Pussycat would disagree with "ontology never finds truth" or that "truth is hidden from us" (not always, tho). I put it this ways because it looks like we agree more or less on "bottomlessness"

But then that's to show how these terms warp around one another more than its an interpretation of the text at hand, no?

We are, after all, still in the introduction :D

Maybe some relativism to the text is worthy to pursue together? Whether we think this or that way?